Associated Press PhotoThe water that comes from your faucet may soon be coming from New Jersey.

STATEN ISLAND, N.Y. -- A deteriorating aqueduct that supplies the city from an upstate watershed is leaking millions of gallons of water a day, and when it is shut down for repairs, alternate water sources may be needed, including from New Jersey.

As officials evaluate how to replace that precious water, there's some concern that what might comes out of Staten Islanders' taps won't taste like the Big Apple's world-famous agua.

"Anybody can tell you they go to New Jersey and they taste the water and it stinks," said Nicholas Dmytryszyn, Borough Hall's environmental engineer.

The city is already preparing the billion-dollar project that will shut down the Delaware Aqueduct for up to a year in 2018 and 2019 to install a two-and-a-half-mile-long bypass tunnel upstate. Test borings are currently under way in Newburgh in Orange County.

Completed in 1944, the 85-mile-long aqueduct supplies more than 500 million gallons of water each day to the city -- just over half of its drinking supply. The remaining water comes from the Catskill Aqueduct.

The leaks in the Delaware Aqueduct were first discovered in 1988. About 15 million to 35 million gallons of water escape each day through the cracks.

To compensate for the Delaware Aqueduct water, the city Department of Environmental Protection (DEP) plans to obtain about 290 million gallons of water each day from the New Croton Aqueduct in Westchester County. That supply is only used as a backup, until a filtration plant is finished next year in the Bronx.

Officials are also mulling whether to pipe in water from New Jersey, Nassau County and, possibly, an underground aquifer in Queens. And while a DEP spokesman assured that any alternate sources will meet all federal standards, some question whether that water will flow over the tongue as agreeably as the city's renowned H2O.

"I don't think the city is going to be shirking any responsibilities," said Dmytryszyn. "One thing the city doesn't want to have on its back is a violation of [federal] drinking-water standards. I think they'll be even more conservative. [Water's] a basic necessity of life. But I'm not going to be absolutely sure the taste will be the same." NO DECISION YET

Farrell Sklerov, a DEP spokesman said recently the agency has made no decision regarding alternate water sources. Factors under consideration include cost effectiveness and construction to pipe in the water.

Officials are also weighing upgrades of the Catskill Aqueduct to increase its volume, said Sklerov.

"We're still in the early stages," the spokesman said. "Any source we're looking at would be safe drinking water for the public. It would meet all federal drinking-water standards."

DEP plans to break ground on the bypass tunnel in two years and complete the connection to the Delaware Aqueduct in 2019. The tunnel will run beneath the Hudson River between Orange and Dutchess counties.

The Delaware Aqueduct will be shut down for eight to 12 months during the connection, which is expected to begin in 2018, said Sklerov.

The bypass tunnel and internal repairs will cost about $1.2 billion, he said. Water projects to supplement the city's supply during part of the construction period will be about $900 million, for a total of $2.1 billion.

Sklerov said officials won't shut down the Delaware Aqueduct until the bypass installation begins to reduce any potential for a collapse.

"It's something we'd look at, but it doesn't seem to be a significant risk," he said.

BEST IN THE REGION

Both Dmytryszyn, the Borough Hall environmental engineer, and Eric Goldstein, a water specialist and lawyer for the Manhattan-based Natural Resources Defense Council said they're glad DEP is planning so far in advance.

Goldstein said water conservation and increasing the Catskill Aqueduct supply could obviate the need to seek alternative sources. Another potential untapped source, he said, is the underground springs beneath city subways.

"Conservation can be the key step the public can take to make sure we get the water we need," he said.

Both Goldstein and Dmytryszyn said water from Nassau County and especially the Queens aquifer would need to be carefully scrutinized for contaminants.

Yet any water ultimately added to the city's system would unquestionably be purified to meet federal standards, said Goldstein.

And Staten Islanders might not be able to taste the difference, he said. Alternative sources would be blended with the water from the Catskill and Croton aqueducts.

"The vast majority of the water should come from the city's traditional water sources, which are high-quality sources," said Goldstein. "New York City's supply is by far and away the best in the region."